Underground grade control protocol design: Case study from the Liphichi gold project,Larecaja,Bolivia

Abstract

Grade control programmes aim to deliver economic tonnes to the mill via accurate definition of ore and waste. The foundation of successful grade control is high quality sampling supported by geology and a suitable data management and modelling system. For underground operations sampling methods include chip, channel and panel samples, grab/muck pile samples, and drill-based samples. Grade control strategy is related to mining method and orebody type. Protocols must be designed to suit the style of mineralisation in question. Holistic studies focusing on ore mineralogy and gold particle deportment, size and distribution are required for sample collection and preparation protocol optimisation through ‘Theory of Sampling’ application. Where possible, characterisation programmes should be undertaken early in the life of a project. Appropriate assaying procedures are also required. Programme implementation will require suitably skilled individuals to train and mentor staff. On-going quality assurance/quality control monitoring and review will allow protocols and staff to be updated as required. A case study of protocol design from the Liphichi gold-antimony project in Bolivia is presented.

Keywords

GOLD VEINS GRADE CONTROL SAMPLING METHODS THEORY OF SAMPLING ORE CHARACTERISATION BOLIVIA

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